Koscielny has been on Wenger's radar for some time, as he impressed in the French domestic league, and is understood to have cost the Emirates Stadium club in the region of £10million.

The 24-year-old, who is also eligible to play for Poland, is set to partner Thomas Vermaelen at the heart of the Arsenal defence, taking the number six shirt once worn by former captain Tony Adams.

Wenger was in need of cover at the back, as Sol Campbell mulls over a new one-year deal while fellow veterans William Gallas and Mikael Silvestre are set to leave after the end of their contracts.

Currently at the World Cup in his role as media pundit for French TV, Wenger believes Koscielny has all the attributes needed to become a successful member of the Arsenal squad seeking to end a five-year trophy drought.

"We identified him as a very strong centre-half, who has made big progress very quickly," said the Gunners boss.

"He has shown he is mentally strong, he's a fighter and a very strong competitor. Koscielny is a great addition to our squad."

The former Tours player is, meanwhile, relishing the challenge of such a step up in class.

"I will have to adapt and give everything in training to get to the level for the Premier League," Koscielny said.

"It's the start of a new adventure. I will give my maximum to play in the team."

Most of Arsenal's players have now returned to the club's Hertfordshire training complex this week ahead of the traditional pre-season friendly at Barnet on July 17, although those who have been in international action will get extra time off, with captain Cesc Fabregas - a target for Barcelona - having joined Dutch striker Robin van Persie in the World Cup final after Spain beat Germany.

Wenger has already secured the capture of long-term target Marouane Chamakh, the Morocco striker, to bolster the Arsenal attack, which could be missing Nicklas Bendtner ahead of their opening game of the new Barclays Premier League season at Liverpool on August 15.

Fulham's Australia international Mark Schwarzer has been linked with a switch to the Emirates Stadium should Wenger decide he needs a more reliable pair of hands in goal next season.

The Gunners boss will waste no time on his return to England after the World Cup final, with the squad set to head out to their Austrian training base before the Emirates Cup at the end of the month.

By then, Wenger will want Fabregas' future decided one way or another, as Barcelona appear to be growing impatient in the pursuit of their former trainee - one which new president Sandro Rosell maintains will not come at any cost.

"We would not pay the 50-60million euros that I have read about," he said.

"If Arsenal do not go crazy, he might play at Barca."